Device for indicating and recording the quality of smoke



Dec. 16, 1930. F. sAwFoRD ET Al. 1,785,392

DEVIdE FOR INDICATING AND RECORDING THE QUALITY OF SMOKE Filed March 28, 1927 alumna im Patented Dec. I6, 1930 FRANK SAWFORD AND FRANK SAWFORD,

PATENT OFFICE JR., OF VANCOUVER, BRITISH COLUMBIA,

CANADA DEVICEFOR INDICATING AND RECRDIN G THE QUALITY F SMOKE Application lcd March 28, 1927. Serial No. 178,963.

This invention relates to devices for indicating thedensity of smoke emitted from a :furnace flue or the like and particularly to instrumentalities assuring reliable and accurate indications over a long period of time.

It is an object of the present invention to provide an apparatus for indicating the density of smoke which will give an absolute measurement of the smoke density and provide a permanent record of its quality over a period of time, and which will eliminate the guesswork of the human element and be independent of weather conditions.

In accordance with the present invention suitably amplified or magnified for indicat lng upon a recorder or indicator;

The invention will be more clearly understood from the following description taken in conjunction with the accompanying drawings: in which,

Fig. 1 is a diagrammatic view of an apparatus embodying' the invention;

Fig. 2 is a sectional elevational view of a flue in which is arranged a source of light and a light sensitive instrumentpfor receivmg a ray transmitted through smoke in the flue; and

F ig. 3 is a sectional view taken upon the line 3 3 of Fig. 2.

One embodiment of the invention is illustrated in the drawings and comprises a tube 10 which is mounted in suitable openings 11 upon opposite sides of a iiu'e 12 so as to extend a short distance from either side thereof. The tube 10 is suitably held in position relative to the flue 12 by rings 13 secured upon the tube adjacent opposite sides ofthe flue by set screws 14. A suitably calibrated transverse opening 15- is provided ina portion of the tube within the flue so as to provide a path of uniform cross-sectional area for the passage of a stream of smoke which will be 50 representative of the quality of the smoke a source of light is arranged to throw a ray passing through the Hue at all times. A suitable source of light, such as an electric lamp 17, connected with a source of electrical supply is positioned in a mounting 18 carrying reflector 1 9 so as to throw a ray of light substantially perpendicular to the stream of smoke passing through the opening 15 in the tube 10, Preferably, the mounting 18 for the lamp 17 is held in spaced relatlon from one end of the tube. For this purpose the mounting 18 is secured upon a link 2O which is pivotally mounted upon a pin 21 on a rilig 22 which is held in spaced relation with the end of the tube`10 by integral lugs 23 which are fastened near the end of the tube 10 inl any appropriate manner, as by set screws 24.-

Preferably, the ring 22 is provided with a suitable bearing 25 of rubber, felt or the like for the rim of the reflector 19 which is held thereagainst by a spring 26 extendin between the-link l20 and the ring 22. The amp 17 may be adjusted relative'to the Ireflector- 19 so as to throw parallel ra s into the tube Ll0 by a suitable adjuster, suc as a screw 27.

A suitable light sensitive instrument, such as a photo-electric cell 30, is positioned in an adjustable mounting in alinement with the lamp 17 and the stream of smoke passing through the opening 15 in the tube v10. For this purpose the cell`30 is held in a tube 31 slidably mounted in a hole 32 in a'ball 33 havin a radial slot (not shown) cut from one side of the peripheral surface to the hole 32. The ball 33 engages suitable bearing surfaces 34 and 35 upon rings 36 and 37.1espectively which are held in position against the ball 33 by clamps 38. The ring 37 is suspended from a pair of rods 38 by means of arms 39 ad'ustably mounted thereon. The rods 38 are eld by a ring 40.mounted upon the end of the tube 10 by set screws 41. A housing 45 is supported upon the ring 37 and surrounds the cell 30 so as to shut oli" all light except that passing through a window 46 disposed at an appropriate point therein 'to permit the passage'o a .ray transmitted from the lamp 17 through the stream of smoke. In order that the ray transmitted through the stream of smoke may be properly concentrated upon the cell 30, a. lens 47 4 are milliamperemeters of any well knownY is suitably mounted in a shroud 48 which protects the lens from dirt and dust and is adjustablymounted upon an arm 50 extending from the ring 40 and heldtherein by av set screw 51. l

The lamp 17 may be supplied with elec.- trical energy from any suitable source of electrical supply, such as the alternating current supply lines 60 and 61. As shown 'in Fig. 1 of the 'drawings the high potential in the lines 60 and 61 is stepped down by a transformer 62 to' supply a current of relatively low potential in the lines 63 and 64 leading to the lamp 17. An adjustable resistance 65 is provided in the` line 64 so as to vary the intensity of the light rays emitted from the lamp 17. These rays are thrown .through the tube 10 so as to strike the stream of smoke passing through the opening 15 substantially perpendicular, and the rays' which are not absorbed by the stream of smoke continua-through the tube 10 as shownby the lines 66 and are concentrated by the lens 47 upon the photo-electric cell 30. The

energy thus generated in the cell 30 is amplified a vacuum tube 70 and transmitted to "an indicator 71 or recorder 72 or both which type embodying a calibrated smoke density scale vas will be described hereinafter. As illustrated in Fig. 2 of the drawings the cell 30 is connected to the vacuum tube 70 byconductors 75 and 7 6, the cathode 77 of the'cell 30 being connected to the rid 78 of the vacuum tube by the connector, while the anode 79 o f the-cell 30 is connected to the anode or plate 80 of the vacuum tube by the conductor 75.' A current of suitable volta e is supplied for heating the filament 81 o the vacuum tube, in order that it emit a stream of conducting electrons, by conductors 82 and 83 leading from the transformer 62. j The conductor 82 may be rovided with a variable resistance 84. An indicating or Vrecording inplate circuit. As illustrated, both the indicator 71 and the recorder 72 are connected in series in the plate circuit by conductors 90, 91 and conductor 92 leading from the recorder to the positive terminal or brush 93 of a rotary convertor 94. The negative potential of this circuit is connected to the filament 81 by a conductor 95 leading from a third brush 96 of the rotary convertor. The negative terminal or brush 97 of the rotary convertor is connected to the rid b a conductor 98 having a suitable a justa le high resistance 99 therein. The rotary convertor 94 is supplied with energy from the lmes 60 and 61'by conductors 100 and 101.

The indicator 71 is provided wlth a pointer 102 movable over a calibrated smoke density scale 73. It will be noted that the scalev 73 is provided with calibrations the tube 10 extending through the clear to dense or from 0 to 100 per cent showing the quality of the smoke which passes through the opening 15 in the tube 10. A marking Oli is also provided on the scale 7 3. If the current supply is interrupted the pointer will move to the 011' portion, but if the indication shows 100 per cent smoke density the apparatus is still working but the light is cut off from the light sensitive cell. The scale 74 may be graduated similarly if desired and is o eratedby a suitable clock mechanism as wil be understood by those skilled in the art.,

' In the operation of the apparatus suitable energy is supplied to the vacuum tube 70 and t e potential y of the grid is adjusted'sc that the pointer 102 is deflected from the olf position to the position marked 100 per cent smoke density. Energy is then 4supplied to the lamp 17 so that its rays are transmitted to the sensitive surface 77 of the photo-electric cell 30 whereupon the electron emission will cause the pointer 102 to be deflected to the position marked 0 .smoke density or clear, provided that no smoke is passing through the flue 12. Should a body of smoke pass through the flue 12 a portion of this smoke will pass through the opening 15 partially or wholly obscuring the light from. the electric cell 30. In such case the electron' emission from the cathode or sensitive surface of the cell 30 will diminish pro-l portional to the amount of light which'penetrates the smoke passing through the opening 15 and should the light be completely obstructed, by dense smoke, the electron emission of the cell 30 will cease. As this electron emission decreases or ceases the current flow through the plate circuit of the vacuum tube will vary proportionally to the 'density ofthe light-which penetrates the smoke body causing a proportional variation in the reading u on, the indicator 71 or the .recorder 73. S ould the light intensity of the beam from the lamp 17 be such that the pointer 102 does not reglster 0 smoke density or clear when no smoke is passing through the flue 12 the intensity of the light beam maybe adjusted by means of the variable resistance 65 until the pointer registers '0 smoke density or clear when the 'lue is free from smoke. A

The photo-electric cell 30 may be adjusted in a suitable position inV alignment with the lamp 17 and stream of smoke to receive the light concentrated from the lens 47 by loosening the clamps 38 so as to permit longitudinal movement of the tube 31 in the ball 33 and universal movement of the ball 33 within its supporting bearings. When the proper adjustment has been obtained the clamps 38 are tightened, thereby clamping. the ball rigidly to the tube 31 as well as holding it securely in proper position upon its bearin and 35 of the rings 36-a11d 37. y providing' ue 12 the surfaces 34 lamp 17 and the photo-electric cell 3 0 are malntained in their correct relation with each other regardless of any distortion of the Hue caused by expansion ,or contraction due to temperature changes on which the equipment" may be mounted.

the Hue 12 as shown by the arrows in Fig. 1.

,-means for enclosing the path tube.

This passage of air serves to`cool the lamp and lens as well as the interior of the tube 10 and keeps the opening 15 free from accu-l mulation of soot.

In the embodiment of the invention illustrated the necessary electricity is supplied to the plate and grid of the vacuum tube by elecvertor, and two separatedesired i potentials may be obtained by adjusting thethird brush 96 with relation to the two main brushes 93 and 97.

If desired, the potential delivered from the source of current supply to the vacuum tube may be checked by a voltmeter in the circuits or the indicator may be constructed, as will be understood by those skilled in the art, with a circuit and switch whereby the potentials of these circuits may be read from the indicator.

Throughout the claims appended hereto we v have employed the terms indicator and indicating to include an indicating or recording device or both.

'What we claim is:

1. In combination, a Huetor smoke passage having two oppositely disposed vopen orifices to permit the entranceof air into the Hue, a source of lightoutside the Hue adjacent one of said orifices, a light-sensitive device outside the Hue adjacent theother of said oril iices, said light source and light sensitive device being aligned with said orifices and spaced therefrom to provide an annular passage between said oriHces and theoutside air, an indicator, electric connections between'the klight-sensitive device and said indicator, and of the ray through the Hue except for a predetermined distance. 2. The combination with a Hue having oppositely disposed orifices,

aligned with said orifices, trical connections between device and indicator, ward from each of said orifices, and means permitting the passage of smoke from said Hue across a predetermined portion 4of the an indicator, electhe light sensitive a tube extending intricpl connections betweenthe light sensitive device and indicator, a tube extending inwardlyand outwardly from each of said oriices, means permitting the passage of smoke from said Hue across a'predetermined portion of the tube, and means for connecting said light source and said light sensitive ,device to i the opposite outer ends of said tube in spaced relation thereto. n

In testimo y whereof we aiiix our signatures. A

' FRANK SAWFORD.

FRANK SAWFORD, JR.

.trol-mechanical means,'such as a rotary conof a light source j and a light sensitive. device adapted to be 3. The combination with a Hue having op- I o`f a light source 

